General color filter substrates include color filters of a plurality of colors arranged in a regular pattern on a substrate such as a glass substrate. Some color filters are placed for each element unit for color display, called pixel, and the typical color combination of color filters is three primary colors, red (R), green (G), and blue (B).
The primary process for the production of color filters is photolithography. In order to produce color layers, this process involves repeating a cycle consisting of application, exposure, development, and baking for the number of times corresponding to the number of colors.
In contrast, an inkjet process can save the time required to finish the entire process because layers of different colors can be produced in a one-stage procedure by using an inkjet apparatus provided with a plurality of heads, specifically by applying inks of different colors from the respective heads. A further advantage of the inkjet process is that this process does not need exposure and development because inks can be applied only to desired regions.
The following are some examples of conventional modified inkjet processes: a process in which pixels are respectively colored with desired colors by controlling the position of a plurality of ink ejecting nozzles and the inter-nozzle distance under certain conditions in relation to the distance between pixels (e.g. Patent Literature 1); a process in which colored regions are produced by using an inkjet head provided with a plurality of nozzles and applying inks to to-be-colored regions more than once by using different nozzles for each application (e.g. Patent Literature 2); a process involving performing multi-stage ink application to to-be-colored regions while running an inkjet head (e.g. Patent Literature 3); and a process for producing colored layers which involves steps of application by an inkjet method and pre-curing of applied materials, and repeating these steps (e.g. Patent Literature 4).